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View Full Version : 200A. Do I have to buy special aluminum wire to bury in schedule 40 to my house?


harfar
Oct 29, 2007, 05:32 PM
I need to move the meter base off my house so it will be much more convenient for me to work on the outside of the house. I want to move the meter base to the utility pole about 90 feet from the house and bury the electrical wires between the house and the pole.

Currently, there are 3 aluminum wires that run from the step-down transformer on the utility pole to the meter base on my house.

A guy from the electric utility said that I need to bury schedule 40 pipe in the ground and use schedule 80 on the verticals, above the ground. He said I then need to buy some special burial wire that comes with 3 wires all bundled together.

I asked him if I could just use the aluminum wire that is already running to the house since I will be burying it inside schedule 40 pipe. He said it would not work because it would not last.

Can someone please tell me the low down? Thanks very much.

tkrussell
Oct 30, 2007, 02:45 AM
First, once you relocate the meter to the utility pole, the main disconnect should need to be located there also. Check with the utility and the local inspector to confirm this.

If the Main does get relocated to the pole, then 4 wires will be needed. If the Main gets to remain in the panel, and the meter alone is on the pole, then 3 wire will be sufficient.

Local codes and condition may not allow aluminum conduit. Again check with local codes. There should be no problem with burying Al conduit, but, soil conditions, such as being close to the ocean, may corrode aluminum.

PVC will be much cheaper and easy to install.

If you install a complete conduit system, with elbows, fittings, etc, then I would not pull a 3 wire twisted cable, it will be too difficult to pull this cable unless the conduit is grossly oversized. I would use pulled individual conductors, aluminum wire with XHHW insulation, or copper with THHN/THWN or XHHW insulation.

If the conduit is only used as a sleeve, and the cable will be exposed directly to earth, then you must use USE insulation. This can be individual conductors, or the multi-wire twisted cable, called URD cable.

Word to the wise, don't just take some guy's word for anything, ask the utility for their Installation Requirements, usually published as a booklet.